The invention relates to a method for producing hybrid particles based on nanoscale SiO2 particles and on polymers, and to a dispersion which is obtainable by the method according to the invention.
Polyacrylates and polymethacrylates are long known in the prior art. They are used by way of example for producing plexiglass or so called acrylate rubbers.
Pure chemical crosslinked polyacrylates have only comparatively low strength. The mechanical properties of polymers can be improved by using fillers. Because acrylate ester groups are comparatively easy to saponify, there are only a few fillers that can be used with polyacrylates, an example being carbon black. However, carbon black impairs the transparency that is frequently desired in polyacrylates.
EP 1 216 262 describes a method for producing an aqueous dispersion of particles, which are composed of polymerizate and of fine inorganic solid.
EP 0 505 230 A1 describes mixed particles which are composed of a polymer matrix which in each case envelops an SiO2 particle. Angewandte Makromolekulare Chemie 242 (1996) 105-122 describes the production of latex particles by emulsion polymerization of ethyl acrylate in the presence of functionalized and non-functionalized SiO2 particles.